To evaluate the validity of the ActiGraph accelerometer (AG) to differentiate between standardized, physical activity tasks using oxygen consumption (
O2) as the criterion measure in children and adolescents with an acquired brain injury; to determine vector magnitude activity intensity cut-points; to compare performance of cut-points to previously published cut-points.
Twenty-seven children performed standardized walking and stepping activities wearing a portable indirect calorimeter, AG, and heart rate monitor. Differences in
O2 and AG vector magnitude activity counts were measured during activities. Receiver operating characteristic curves were determined for intensity cut-points.
O2 and AG activity counts significantly increased as walking speed increased. Discrimination of the newly derived cut-points was excellent and demonstrated greater agreement compared with the previously published cut-points.
Output from accelerometers can differentiate physical activity intensity in children with an acquired brain injury. Future studies can apply these cut-points to evaluate physical activity performance.
The validity is examined of the ActiGraph® accelerometer to differentiate between standardized physical activity tasks using oxygen consumption as the criterion measure in children and adolescents with an acquired brain injury.
Queensland Cerebral Palsy and Rehabilitation Research Centre (Drs Baque, Sakzewski, Boyd, and Barber), Child Health Research Centre, Faculty of Medicine, The University of Queensland, Brisbane, Australia; Institute of Health and Biomedical Innovation at the Queensland Centre for Children's Health Research (Dr Trost), School of Exercise and Nutrition Sciences, Queensland University of Technology, Brisbane, Australia.
Correspondence: Emmah Baque, PhD, Queensland Cerebral Palsy and Rehabilitation Research Centre, The University of Queensland, Centre for Children's Health Research, Level 6, 62 Graham St, South Brisbane, Queensland 4101, Australia (firstname.lastname@example.org).
Grant Support: This project is supported by the Queensland Government Smart Futures Co-Investment Fund; Perpetual Foundation—The Aldred Charitable Endowment, Margaret Augusta Farrell, Williams HP Trust Fund, Love JS, and The Jessica and Wallace Hore Foundation (FR2012/0796); and Financial Markets for Children (2011-210). The Queensland Cerebral Palsy and Rehabilitation Research Centre is supported by the Merchant Charitable Foundation via the Children's Hospital Foundation (Donation ID 10415). EB is supported by an Australian Postgraduate Award. LS is supported by Australian National Health and Medical Research Council (NHMRC) Early Career Fellowships 1090828 and 1036183. RB is supported by NHMRC Research Fellowships 1037220 and 1105038. LB is supported by an NHMRC Early Career Fellowship 1070623.
The authors declare no conflicts of interest.